Air-pump for evacuating air from condensers, refrigerating plants, and the like



B. AND F. LJUNGSTRD'M. AIR PUMP FOR EVACUATING AIR FROM CONDENSERS, REFRIGERATING PLANTS, AND THE LIKE.

APPLICATION FILED SEPT-l4. 1917- 1,343,922.

Patented June 22, 1920.

WWW

UNETED *s'mrss PATENT OFFICE.

ZBIRGER LJ'UNGSTBbM,

HOLM, SWEDEN.

or STOCKHOLM, AND FREDRIK LJUNosTRoM, or FINsroNa, SWEDEN, ASSIGNOBS T0 AKTIEBOLAGET LJUNGsTRoMs ANGTURBIN, OF STOCK- AIR-PUMP FOR EVACUATING AIR FROM CONDENSER/S, REFRIGERATING PLANTS, AN D THE LIKE.

Application filed September 14, 1917.

To all whom it may concern:

Be it known that we, BIRGER LJUNGSTROM and FREDRIK LJUNes'rRoM, sub ects of the King of Sweden, residing at Stockholm and F inspong, in the Kingdom of Sweden, have invented certain new and useful Improvements in Air-Pumps for Evacuating Air from Condensers, Refrigerating Plants, and the like, of

which the ibllo'wing as a specification.

The present invention has reference to that class of air-pumps for evacuating air from condensers, refrigerating plants and the like, which operates with. two or more steam injectors connected in series and the invention is mainly characterized by the fact that behind each steam injector there is arranged a surface condenser for condensing the steam used in the steam-in ector.

The invention is illustrated in the annexed drawing in which D Figure 1 shows in side elevation the air pump and a condenser combined therewith which is to be exhausted.

Fig. 2 is a section of the pump on an en larged scale.

In said drawings 1 indicates the condenser to be evacuated or air, 2 the air dischargepipe of said condenser, 3 a pump for the water of condensation and 4c the air-pump forming the subject of the invention. This air-pump consists of a number of steam-1njectors 5 (of which four are shown in the drawings) arranged 1n series, and to which steam is supplied from a suitable source or sources.

The first or lowest steam-injector 5 opens into a chamber 6, connectedwith the air discharge-pipe 2 of the condenser said chamber also communicating with and being connected to a surface-condenser 7, so that the steam from the injector 5 together with the air drawn from the discharge-pipe 2 pass through the said surface-condenser 'Z.

. The outlet from the latter is connected with another chamber 6, into which the next in jector 5 opens, and this chamber is in turn connected with a surface-condenser arranged above the first, and so on to the top. 'fhe arrangement is such, that the steam from every injector and the air drawn away are forced to pass all the following surface-condensers in succession, as indicated by the Specification of Letters Patent.

pass.

Patented June 22, 1926, Serial No. 191,392.

arrows, drawn in full lines in Fig. 2. The surface-condensers are provided in known manner with tubes 18, inserted between tubcplates and through which the steam and air When passing through these surface condensers the steam, forced in by the injectors, is condensed and at that end of every surface-condenser 7, remote from the injector there is arranged a chamber 8, communicating with the steam and air passages 1n the surface condenser, in which chamber the water of condensation is collected. These chambers are arranged in series above each other as shown in Fig. 2, and in the bottoms or partition walls between the chambers are arranged calibrated holes 10 of suitable size, so that the water of condensation in all the chambers 8 finally passes through the lowest of these chambers. The arrangement is such, that the sectional area of these channels may be altered according to the. prevailing circumstances. From the lowest'chamber 8 the water of condensation is discharged at the outlet 9. Also from that end of the airpump, which lies nearest the injectors, a discharge pipe 11 is led for water of condensation from the steam of the injectors. The air is discharged at the top through the outlet 1?. The water of condensation from outlet9 and pipe 11 may obviously be led wherever it may be useful in the apparatus.

The cooling water for the surface-condenser 7 enters at the lower side of the first or lowermost surface-condenser through the inlet 12 and is discharged from the last or uppermost condenser through the outlet 19. Condensation water from the pump 3 is preferably used as the cooling medium and between this pump and the inlet 12tl1ere is therefore arranged a pipe 13. The sur face-condensers '4' are each divided in two compartments by means of a partition wall is, leaving openings or channels 15 between the water chambers of these two com.- partments and the openings or channels between the water chambers of two adjacent surface-condensers are designated by the reference character 16. The openings 15 and 16 are so placed that all the water-chambers are connected in series whereby the cooling water passes through all the chambers in succession as indicated by the arrows drawn in broken lines. The surface-condensers 7 are so constructed or shaped that as they progress upward they have a smaller sectional area than the one immediately below, the purpose of this arrangement being to obtain a suitable velocity of the gas streaming through the condensers. The partition walls 14, which subdivide each surface-condenser into two com-' 'p artments are further preferably so arranged that a compartment following upon another has a smaller sectional area than the compartment preceding it in order to obtain a suitable velocity of the gas within each condenser. The sectional area of each compartment may also decrease in size from its inlet to the outlet. The surface-condensers may obviously be subdivided into more than two compartments.

As indicated by the arrows in Fig. 2, the liquid and gas currents within each condenser compartment travel in the same direction, that is to say the condensers are constructed on the parallel current principle.

Having now particularly described and ascertained the nature of our said invention,

and inwhat manner the same is to be performed, We declare that What we claim is:--

An air pump for evacuating air from condensers and the like, comprising a plurality of steam injectors and a corresponding series of surface condensers arranged with one surface condenser behind each injector to receive and condense the steam from the latter, the said pump being provided with a series of chambers communicating respectively with said surface condensers to receive the water of condensation therefrom, said chambers being directly connected with each other by calibrated channels and arranged one above another, so that the water of condensation may flow down from chamber to chamber through the series.

In testimony whereof we affix our signatures in presence of two witnesses.

BIRGER LJUNGsTRoM. FREDRIK LJUNGsTRoM.

Vitnesses FRANK LYON, ELIN VVAHMAN. 

